1. Field of the Invention
The invention relates to a knuckle connector for connecting spacedly end knuckles of a chain strand, more particularly to a knuckle connector which is easy to assemble and which has provisions to prevent untimely disengagement of the end knuckles of the chain strand.
2. Description of the Prior Art
In a conventional chain manufacturing process, a chain strand is formed by interconnecting adjacent knuckles thereof by means of rivets. During use, the end knuckles of the chain strand are joined together by means of a rivet so as to form a chain loop. Riveting of the end knuckles by the end user makes difficult the assembly of the chain loop.
In order to overcome the above drawback, a knuckle connector has been developed so as to simplify the connection of the end knuckles. Referring to FIG. 1, a knuckle connector (1) is used to interconnect the end knuckles (21, 21') of a chain strand (2) in order to form a chain loop. The knuckle connector (1) comprises a pair of link units (11, 11'), each of which includes a link pin (12, 12') and a link plate (13, 13'). The link pin (12, 12') includes a shank with a head (121) and a tail end that is formed with a peripheral channel (122, 122'). The link plate (13, 13') is oval-shaped and is formed With a circular through-hole (131) on one end and a retaining hole (132, 132') on an opposite end. The retaining hole (132, 132') has an outline similar to the number "8" and includes a large insert part (133, 133') and a diameter-reduced retaining part (134, 134') that is communicated with the insert part (133, 133'). During manufacture of the knuckle connector (1), the link pin (12, 12') is extended into the circular through-hole (131) in the link plate (13, 13') such that the head (121) of the former is secured in the through-hole (131) of the latter.
Referring to FIG. 2, when the knuckle connector (1) is used to interconnect the end knuckles (21, 21') of a chain strand (2), the link pins (12, 12') of the link units (11, 11') are extended through a pin hole formed in a corresponding one of the end knuckles (21, 21') such that the peripheral channel (122, 122') extends into the insert part (133, 133') of the retaining hole (132, 132') in the link plate (13, 13') of a remaining one of the link units (11, 11'). The end knuckles (21, 21') are then pulled apart so that the peripheral channel (122, 122') of the link pin (12, 12') of one of the link units (11, 11') engages the link plate (13, 13') of the remaining one of the link units (11, 11') in the retaining part (134, 134') of the retaining hole (132, 132') of the latter, thereby forming a chain loop.
From the foregoing, it can be seen that no additional tool is needed to join the end knuckles (21, 21') of the chain strand (2) if the knuckle connector (1) is employed. However, the main drawback of the conventional knuckle connector (1) is as follows:
It is common for two adjacent knuckles to experience oppositely oriented forces when the chain loop is in use. Referring once more to FIG. 2, if the distance between the link pins (12, 12') is instantaneously reduced due to the presence of the oppositely oriented forces, the peripheral channels (122, 122') of the link pins (12, 12') may simultaneously move from the retaining part (134, 134') of the retaining hole (132, 132') to the insert part (133, 133'), thereby causing the untimely disengagement of the link pins (12, 12') from the link plates (13, 13'). Therefore, untimely disengagement of the end knuckles (21, 21') can occur when the conventional knuckle connector (1) is in use.